Similar Minds
by CaTigeReptile
Summary: I'm not sure how to explain this. A peek into the minds of McCoy and Spock during their eternal debate, emotion vs. logic. As if they're mutually exclusive.


I don't own Star Trek, these characters aren't mine, I make no money off of this, etc; Beta reader was Foxcat93 -- Thank you for your help!

* * *

_It's that time again._ Dr. Leonard "Bones" McCoy, Chief Medical Officer aboard the Starfleet ship U.S.S. Enterprise, had just performed First Officer and Chief Science Officer Spock's routine physical, and now has to look through the test results for anomalies.

Despite his apparent track record of valuing feelings over reason, Bones is, as he has to constantly remind everyone who asked him to do inane things, a doctor. In undergraduate school alone, doctors study chemistry, doctors study biology, doctors study physics, doctors study organic chemistry, doctors study physiology, doctors study genetics, doctors study neurology, doctors study microbiology, doctors study biostatistics – doctors study everything except . . . no, doctors study everything.

With an innate curiosity about the mechanics of biological functioning, McCoy has been known to order tests on patients that do not seem directly relevant to improving or evaluating their health. McCoy does not lie about administering these tests in his log; they are easily explained by the medical fact that every individual possesses unique physiological characteristics.

For instance, ancient doctors, or so the literature suggests, used to have arguments about anthronormothermia. Now of course it's a given that these folks were limited by their archaic methods of statistical analysis and lack of standardized measuring locations due to their primitive technology, but they still came up with a golden number range, 37 degrees Celsius, plus or minus point-seven degrees if measured orally. Even worse (though even more understandable given the technology) was the ridiculously narrow temperature range considered to be necessary for normal enzymatic reactions to occur. In truth, body temperatures are affected and individualized by size, weight, metabolism, level of physical activity, and even the circadian rhythm. That means, of course, that determining whether someone has a fever or hypothermia doesn't depend on the number measured, but rather on the up- or downward trend of their temperature compared to their individual core baseline range. The same can be said for anything from cholesterol level to alkalinity of saliva.

There, all testing justified.

Though the CMO always gives the CSO a hard time about his physiology, teasing about how 'weird' it was, it's not like Bones doesn't know how Spock, as an organism, functioned, or why he functioned in that way. For example, McCoy tries to sneak in a quip about Spock's green blood whenever he can, but the doctor knows that it's simply due to a naturally high amount of copper in the (half) Vulcan's blood, much more than the iron content. So when exposed to the air, it's the copper than oxidizes, turning the blood green, whereas in humans it's the high iron content that oxidizes and turns the blood _red_.

Spock's blood pressure, for a human, is impracticably low. This is compensated for by his incredibly high pulse rate. Comparing his circulatory system to that of an average _Homo sapiens_, anyone can tell that his cardiovascular setup is just a different means to the same end, though McCoy still can't figure out why Spock's heart was where it was. The location of the human – or earth-mammalian heart in general – makes plenty of sense: protected by the sternum, right with the lungs and the relative center of the body, thus able to distribute blood to the extremities in the most efficient way possible. The doctor just shrugs it off as a relic of a different evolutionary path.

. . . Which is something that brings up the question that McCoy can't answer, no matter how hard he racks his brain: if humans and Vulcans have such fundamental physiological differences, how could they possible create healthy offspring together? Human babies born with organs positioned out of place must have immediate corrective surgery or they die. The human liver and kidneys can't handle all that much copper – hell, too much copper can cause granule cell apoptosis. Clearly, Vulcans and humans are different even down to the essential amino acids, yet here Spock is, and the only 'human' trait the Vulcan . . . oid seems to carry is his 'emotion' – something that, to McCoy's limited sociological knowledge, is also in the endocrine systems of Vulcans and is simply affected by cultural, hormonal and environmental influences.

Bones doesn't let it bother him too much, though. After all, lions and tigers can make ligers and tigons, though of course their likelihood of congenital defects and a short lifespan are relatively high . . . and, of course, they're sterile.

As the Doctor sifts through data on the first officer's dopamine, endorphin, adrenaline, serotonin, and norepinephrine levels, he realizes that the screen in front of him displays his decisive victory against Spock in their eternal debate over the necessity of emotion.

McCoy expresses his excitement at this epiphany with a "Damnit!"

After all, why didn't he think of this before?

* * *

The CMO is a regular visitor to the starship's bridge room. When there are no patients to treat, no test results to be analyzed, and no research to be done, McCoy gets bored. On top of that, he's a surgeon – a species of animal that, in order to survive, needs to know everything that is going on in its habitat at any given moment. Sometimes, he enters the bridge, hands behind his back, observes, and exits; his patrol is detected by no one.

Spock doesn't count.

Other times, he storms into the bridge, already pacing the room by the time that the door fully opens. This is one such time, and he's bee-lining towards the Vulcan; his intention is obvious.

"It's basic social evolutionary science, Spock. Hell, it's just evolutionary science, social interaction be damned. All animals need it in some form to function."

Spock is 98.92 percent sure of the topic Dr. McCoy wishes to discuss – quite a statistically significant number. That kind of level of certainty naturally points to the conclusion that the good doctor is obsessed with the issue about which they so often debate. In the Chief Medical Officer's case, his obsession is caused by frustration; this frustration is a direct result of his inability to explain his opinions rationally. Frustration is a form of anger, which is an emotion which clouds judgment and critical thinking. Thus, the doctor's arguments lack empirical credibility and any attempts at refining aforementioned argument are rendered inefficient. Spock cannot blame Dr. McCoy for this; the surgeon is a human, and thus has a natural mental disability.

In order to convey this message to the doctor, Spock raises an eyebrow. This elicits a scowl (an outward indicator of a negative emotional reaction) from the primate, who has apparently interpreted his body-lingual response as what is known as an 'insult.'

When any sort of mission or collaboration includes humans, one must expend a large amount of effort into accommodating for their fragile minds. If one does not allow them to enact their social rituals, humans become ineffective. While in theory this seems illogical because human rituals are time-consuming and serve no practical purpose, Spock has learned first-hand that these rituals are not acquired, but rather are a biological necessity for the survival of _Homo sapiens_. Many, if not most, species go extinct despite their apparent advantages, sometimes due to one single fault; thus will be the fate of _Homo sapiens_, as the random path of evolution caused the species to have emotions that limit their potential.

Of course, Spock's Vulcan side neutralizes the faults in his partly human genes.

Spock, in order to prevent inefficiency caused by a functionally-impaired human, must be careful of how he responds to McCoy, or else the doctor will have an emotional reaction that will hinder his efficacy and thus the efficacy of the entire crew. A crew is like a machine: when one servo is knocked out of place, the entire machine ceases to function effectively.

To make things even more difficult, a human may not necessarily be satisfied by what is objectively the most desirable reaction. To take 'Bones' as an example, if Spock were to feign agreement with the doctor, the human would not respond with what theory indicates would be the appropriate emotional response: a variant of happiness. Instead, he would respond with anger, because their ongoing debate is not, in fact, a real debate; instead it is one of the human rituals that must be performed in order for the doctor to function well. If Spock relents, then the debate is over; the ritual can no longer be performed, and the doctor is no longer at peak functionality.

The First Officer notices a change in Dr. McCoy's facial expression; his mouth has turned upward in a smirk (an expression of a complicated emotion; a positive emotion caused by the knowledge that one has elicited a negative emotion from someone else). Such a change is indicative of imminent oral communication.

"What're you smirkin' about, Spock?" drawls McCoy.

Smirking? Once McCoy says that word, Spock can feel that his zygomatic muscle is indeed active. He does not remember consciously activating this facial expression. Such incidences occasionally occur as a side effect of being part human, and if he pays it any mind, his minor human attributes temporarily amplify; luckily this is an inefficiency which he can control.

So, nearly-undetectable smirk still on his face, Spock calmly explains his reason for smiling to the doctor.

"I am simply displaying a non-verbal response to your non-sequitur comment in order to satisfy your instinctual desire for an anthropomorphic social reaction," replied the Vulcan, not even missing a beat.

McCoy raised an eyebrow in return, his own smirk still on his own face.

"Yeah, you keep telling yourself that."


End file.
